diff --git a/lib/reducers/message-reducer.js b/lib/reducers/message-reducer.js
--- a/lib/reducers/message-reducer.js
+++ b/lib/reducers/message-reducer.js
@@ -82,6 +82,7 @@
   threadIsPending,
 } from '../shared/thread-utils.js';
 import threadWatcher from '../shared/thread-watcher.js';
+import { threadSpecs } from '../shared/threads/thread-specs.js';
 import { unshimMessageInfos } from '../shared/unshim-utils.js';
 import { updateSpecs } from '../shared/updates/update-specs.js';
 import { recoveryFromReduxActionSources } from '../types/account-types.js';
@@ -110,7 +111,6 @@
   stateSyncPayloadTypes,
 } from '../types/socket-types.js';
 import { threadPermissions } from '../types/thread-permission-types.js';
-import { threadTypeIsThick } from '../types/thread-types-enum.js';
 import type {
   LegacyRawThreadInfo,
   RawThreadInfos,
@@ -151,7 +151,7 @@
       threadHasPermission(threadInfo, threadPermissions.VISIBLE) &&
       (threadInChatList(threadInfo) ||
         watchedIDs.includes(threadID) ||
-        threadTypeIsThick(threadInfo.type)))
+        !threadSpecs[threadInfo.type].protocol.messagesStoredOnServer))
   );
 }
 
@@ -635,24 +635,25 @@
       payload: {
         threads: Object.fromEntries(
           Object.entries(updatedThreads).map(([threadID, thread]) => {
-            let isThreadThick;
+            let threadType;
             if (threadInfos[threadID]) {
-              isThreadThick = threadInfos[threadID].thick;
+              threadType = threadInfos[threadID].type;
             } else {
               const threadIDParseResult = parsePendingThreadID(threadID);
-              isThreadThick = threadIDParseResult
-                ? threadTypeIsThick(threadIDParseResult.threadType)
-                : false;
+              threadType = threadIDParseResult?.threadType;
             }
+            const messagesStoredOnServer = threadType
+              ? threadSpecs[threadType].protocol.messagesStoredOnServer
+              : false;
             return [
               threadID,
-              isThreadThick
-                ? {
+              messagesStoredOnServer
+                ? thread
+                : {
                     ...thread,
                     startReached:
                       thread.messageIDs.length < defaultNumberPerThread,
-                  }
-                : thread,
+                  },
             ];
           }),
         ),
diff --git a/lib/shared/threads/protocols/dm-thread-protocol.js b/lib/shared/threads/protocols/dm-thread-protocol.js
--- a/lib/shared/threads/protocols/dm-thread-protocol.js
+++ b/lib/shared/threads/protocols/dm-thread-protocol.js
@@ -574,6 +574,8 @@
   },
 
   shouldPerformSideEffectsBeforeSendingMessage: false,
+
+  messagesStoredOnServer: false,
 });
 
 export { dmThreadProtocol };
diff --git a/lib/shared/threads/protocols/keyserver-thread-protocol.js b/lib/shared/threads/protocols/keyserver-thread-protocol.js
--- a/lib/shared/threads/protocols/keyserver-thread-protocol.js
+++ b/lib/shared/threads/protocols/keyserver-thread-protocol.js
@@ -370,6 +370,8 @@
   },
 
   shouldPerformSideEffectsBeforeSendingMessage: true,
+
+  messagesStoredOnServer: true,
 });
 
 function mediaIDIsKeyserverID(mediaID: string): boolean {
diff --git a/lib/shared/threads/thread-spec.js b/lib/shared/threads/thread-spec.js
--- a/lib/shared/threads/thread-spec.js
+++ b/lib/shared/threads/thread-spec.js
@@ -275,6 +275,7 @@
     +pendingSidebarURLPrefix: string,
   },
   +shouldPerformSideEffectsBeforeSendingMessage: boolean,
+  +messagesStoredOnServer: boolean,
 };
 
 export type ThreadSpec = {